Fujitsu and Japan's leading technology research institute RIKEN have just announced the successful development of a new 256-qubit superconducting quantum computer, promising to significantly increase the country's quantum computing capacity. Fujitsu said the system will be located at the RIKEN RQC-FUJITSU Collaboration Center, and apply high-density deployment techniques.
This new quantum computer is essentially an upgrade and development of the previous 64-qubit version, also jointly developed by Fujitsu and RIKEN. With four times the number of qubits, it is capable of analyzing larger molecules and supporting advanced error-correction algorithms.
Fujitsu and RIKEN will not have exclusive access to the new 256-qubit computer, but plan to open access to global businesses and research institutes from the first quarter of fiscal 2025 (starting April 2025) to advance scientific projects.

In addition to the increase in qubits, there have been notable breakthroughs in cooling technology for the computer. The cooling efficiency of the system is said to have reached its optimal state thanks to "dilution refrigerator" technology that combines high-density deployment techniques and cutting-edge thermal design.
In the future, Fujitsu and RIKEN aim to enhance the ability to seamlessly interact between quantum and classical computers, allowing users to run hybrid (quantum-classical) algorithms. At the same time, the two units are also collaborating on the development of another 1,000 qubit computer system expected to be launched next year.
Although 256 qubit computers are no longer the market leader (1,000+ qubit systems exist), testing different approaches is necessary, as some may not scale to practical applications.